I think Africans in general wants these anti gay laws and that include South Africa; given the killings of gays, the stigma associated with gays especially among Africans, also if you notice these guys who abuse gays in townships where where mostly Africans live, almost no one reports such incidents and that means black people support such killings.

My reasoning is that South Africa is seeking crumbs that fall from the American tables (investors) that they are in favor of gay laws.

Correctly I think also South Africa is most likely to join their neighbors in these anti gay laws given the African Union doesn't exclude the countries that favor such laws and could mean African Union itself is in favor such laws.

Now should South Africa adopt anti gay laws as-well, what could be the future of the African Continent?